Here's the law of unintended consequences in action. A rocket scientist and U.S. Army officer with some level of security clearance assists in building up the American space program. Despite a seemingly exculpatory series of actions—including marrying the daughter of a prominent anti-communist in his native country and an application to become a U.S. citizen—the FBI, working from a Communist Party document that lists him as a member, suspects that he's a red. He fights this charge for four years but is finally deported to his native country, which is now under the control of a murderous communist dictator. There he becomes the father of the country's space program, and lives long enough to see it put a man into space. It's the strange case of Tsien Hsue-shen.
(Easterbrook alert: The article calls the fiendish Dr. Hsue-shen "an enigma.")
Were the charges legit? Was the CP document a plant? Did anti-communist hysteria give the commies an asset the U.S. might have kept? The article mentions a book by Iris Chang. Anybody read it?